P. Rajagopalan, U.S. Pat. No. 4,438,120, describes 1,2,3,4,8,9-hexahydropyrido[4',3':2,3]-indolo[1,7-ab][1,4]benzodiazepines and 1,2,3,4,4a,8,9,14a-octahydropyrido[4,3,:2,3]indolo[1,7-ab][1,4]benzodiazep ines useful as tranquilizers.
Cohen, et al., U.S. Pat. Nos. 3,373,168 and 3,457,271, describe 1,2,3,4,8,9-hexahydropyrido [4',3':2,3]indolo[1,7-ab][1]benzazepines and 1,2,3,4,4a,8,9,14a-octahydropyrido[4',3':2,3]indolo[1,7-ab][1]benzazepines useful as antidepressants.
Adams, U.S. Pat. Nos. 3,932,650 and 3,983,123, describes 1,2,3,4,4a,8,9,14a-octahydropyrido [4',3':2,3]indolo[1,7-ab][1]benzazepines useful as CNS depressants and analgesics.
Berger, U.S. Pat. Nos. 3,890,327 and 4,018,930, describes trans-1,2,3,4,4a,8,9,14a-octahydropyrido [4',3':2,3]indolo[1,7-ab][1]benzazepine and its 3-substituted derivatives useful as sedative/tranquilizers.
Blumberg, U.S. Pat. No. 3,790,675, and Finizio, U.S. Pat. No. 3,764,684, describe 1,2,3,4,8,9-hexahydropyrido[4',3':2,3]indolo[1,7-ab][1]benzazepines useful as analgesics, anxiolytics and antipsychotics.
W.H. Linnell and W.H. Perkin, Jr., J. Chem. Soc. 1924, 2451 describe the preparations of 1,2,3,4,8,9-hexahydrocarbazolo[1,8-ab][1,4,]benzodiozepin-8(oH)-one.
Traditional neuroleptic antipsychotic drugs include butyrophenones, phenothiazines, thioxanthenes, and diphenylbutylpiperidines. These traditional drugs suffer from the disadvantage of causing neurologic side effects, e.g., extrapyramidal symptoms and tardive dyskinesia, in humans at therapeutically effective doses.
An objective of the present invention is to provide therapeutically effective antipsychotic drugs with reduced neurologic side effects. The present invention provides antipsychotic agents that are structurally dissimilar to traditional neuroleptic antipsychotic drugs. Based on the structural differences between compounds of the present invention and traditional neuroleptic antipsychotic drugs such as haloperidol and chlorpromazine, compounds of the present invention are expected to have a reduced propensity to induce neurologic side effects in humans at therapeutic doses.